<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>Document</title>
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<body>

</body>

</html>
<script>
  //判断两个数字的大小
  var a = 10;
  var b = 20;
  if (a > b) {
    console.log('第一个数字比较大，它的值是：' + a);
  } else {
    console.log('第二个数字比较大，它的值是：' + b);
  }
</script>